Generation of storage stability data for agricultural chemical products

Agricultural chemical products can undergo chemical and physical changes on storage. The rate at which these changes occur depends on the nature of the active constituent(s), the non-active components, the formulation type, the packaging and, notably, the storage conditions (temperature, light and humidity). The product remains fit for use as long as these changes have no adverse effects on application, biological performance, or the safety of operators, consumers or the environment.

This guideline provides a comprehensive guide to the conduct of stability testing for agricultural chemical products. The Australian Pesticides and Veterinary Medicines Authority (APVMA) stability testing guideline has been constructed to closely follow the Manual on the development and use of FAO and WHO specifications for pesticides (JMPS 2010) (FAO/WHO pesticide specifications). The OECD Guidance Document for Storage Stability Testing of Plant Protection and Biocidal Products is also noted, however, it provides a high level overview of storage stability data, and is not an alternative or replacement for this guideline.

1. Generating storage stability data

Storage stability data should be generated with the product stored in the proposed commercial packaging (or smaller packages of the same construction and material), under accelerated conditions, and/or real-time testing at room temperature, or under ambient warehouse conditions. The following information regarding the storage stability trials should be supplied to the APVMA:

• Product specifications, with proposed limits for the content of active constituents and physical characteristics of the product within which the properties of the product will remain during its proposed shelf life. Products may have different specified limits at batch release, and at the end of its shelf life.
• Test results generated before and after storage, including full details of the methods used to produce data for each of the test parameters listed in the shelf-life specifications.
• Data describing the stability of the packaging materials demonstrating no significant deterioration, as interaction with a product can cause brittleness, softening, and corrosion of packaging.

Most agricultural products are not date-controlled under APVMA legislation, unlike veterinary products. For the majority of agricultural chemical products, data should confirm that the formulated product will remain within specification for at least 2 years when stored in its unopened, original container, away from direct sunlight, and at or above 25˚C (‘normal storage conditions’).

Products containing some specific agricultural active constituents are designated as date-controlled products under legislation, have approved shelf lives, and must carry expiry dates on the label. For further information, see the separate guideline on date-controlled agricultural chemical products. For a product not designated as date-controlled, a shelf life of less than 2 years (including an expiry date on the label) may be approved where the data are not sufficient to confirm that the product will remain within specification for at least 2 years, under normal storage conditions.

1.1. Pack sizes and pack size changes

As specified below in section 2, stability testing trials for new products should be conducted on product packaged in the same containers (materials and pack size) that are proposed for the marketing of the product. Smaller containers of the same material as the commercial containers may be used for stability testing, where the size of the commercial container makes stability testing impractical.

Applicants may also wish to market their products in a smaller container at a later date. Undertaking a stability study in a smaller container of the same material and construction would demonstrate the product pack size is fit-for-purpose for not only the current marketed product size, but for future, smaller pack sizes.

Packaging size (net contents) is a relevant particular for products under APVMA legislation, and pack sizes additional to those currently registered require an application for variation of the product registration. Depending on the situation, stability data may be required to support the new pack size(s).

1.1.1. Increased pack sizes

The APVMA does not require additional stability data for an increase in primary pack size from that used in the stability study. The surface area to volume ratio of the product reduces as the primary pack size increases, and the interactions between the product and packaging become less significant.

Larger pack sizes may have implications for other assessment areas (for example, worker safety or environmental impact), and data or argument may be required to address those potential risks.

The packaging for a larger container must meet the conditions of registration for containers in terms of having sufficient strength to prevent leakage, and must be of a practical size to allow users to comply with any label instructions, such as 'shake well before use'.

1.1.2. Decreased pack sizes

Smaller pack sizes have a greater ratio of surface area to volume than larger containers, interactions between the product and packaging are generally more significant, and stability data or scientific argument in-lieu of data may be required to support a smaller pack size.

Approval of a pack size 50% smaller (by volume, or by weight) than the pack size used to generate the stability study data will be considered by the APVMA without provision of further stability data, provided there are no known stability problems with the active constituents and/or formulation in question. For example, it is very unlikely that a smaller pack size of a date-controlled product would be supported without further stability data.

In addition, where a long history of use of other registered products with the same formulation type and active constituent in smaller pack sizes exists (for example, soluble concentrates containing 450 g/L glyphosate as the isopropylamine salt), it may also be possible to support a smaller pack size without stability data. A scientific argument on the registration history of similar products in smaller packs could be provided in lieu of stability data, and would be accepted by the APVMA if there was sufficient evidence of stability based on registrations of other products.

1.2. Packaging materials – new product registrations

Stability data should be generated for the product while stored in its proposed, commercial packaging. When multiple packaging materials are used for a product, or where a reference product uses a different packaging material even with an identical formulation, stability data should generally be provided for the product in each packaging material.

However, certain packaging materials are more resistant to corrosion as a result of product interaction, than others. Where the stability has been demonstrated for a less chemically resilient material, and it is proposed to add or change to a material known to be more resistant to chemical degradation, stability data would not be required for the more resilient packaging material.

Acceptable extrapolations from data generated for particular packaging materials are detailed below.

1.2.1. Liquid formulations

Table 1

Water based formulations, e.g. aqueous soluble concentrates and suspension concentrates
Packaging used in the stability study	Acceptable extrapolations
Non-metal	All non-metal packaging types are supported with no further data
Organic solvent based formulations, eg emulsifiable concentrates, non-aqueous soluble concentrates
High density polyethylene (HDPE)	HDPE/EVOH, fluorinated HDPE and HDPE/polyamide packs are supported with no further stability data
HDPE/EVOH or fluorinated HDPE or HDPE/ polyamide	Full stability data from one of these 3 packaging types can be extrapolated to one of the others, or to plain HDPE, with the provision of seepage data, i.e. packaging stability data, which requires only observation of the effects on the packaging during storage, not testing against all the product specifications, and can be conducted as a real-time or accelerated study

1.2.2. Solid formulations

Extrapolation is possible between all container types except:

• to or from packaging involving water-soluble bags; and
• from rigid to flexible containers for granular products due to potential issues with crushing of granules if containers are stacked.

1.3. Changes to packaging materials for registered

For registered products, packaging material (unlike pack size) is not a relevant particular, and therefore a change to packaging material by itself does not require an application for variation of registration.

However, registrants should note that under Regulation 18 of the Agvet Code Regulations, it is a condition of registration that products must only be supplied in containers that meet the following requirements:

a) Are impervious to, and incapable of, chemical reaction with the contents when under conditions of temperature and pressure that are likely to be encountered in normal service; and

b) Have sufficient strength and impermeability so to prevent leakage of its contents during handling, transport and storage, under normal handling conditions; and

c) If it is intended to be opened more than once – be able to be securely and readily closed and reclosed; and

d) Have sufficient excess capacity to prevent it from breaking if its contents expand during handling, transport or storage; and

e) Enable all or any part of its contents to be removed or discharged in such a way that, with the exercise of no more than reasonable care, the contents cannot:

i. harm any person; or
ii. have an unintended effect that is harmful to the environment.

Changes to packaging materials in accordance with 1.2.1 and 1.2.2 above would comply with Regulation 18. A change to packaging materials other than those detailed in sections 1.2.1 and 1.2.2 may not comply with Regulation 18. Such a change without scientific data may not continue to satisfy the safety criteria. Therefore, for changes to packaging materials other than those in section 1.2.1 and 1.2.2, registrants should generate stability data for the new packaging to confirm that it is sufficiently resilient, and the product will continue comply with the conditions of registration specified in Regulation 18.

1.4. Shelf-life statement on the product label

Printed product labels should include the date of manufacture (month and year) of a batch, and relevant information on the conditions under which the product should be stored. For agricultural chemical products, an expiry date is normally only included on the product label if the product cannot be stored for at least 2 years at or above 25˚C, or if the product is date-controlled under APVMA legislation. A list of date-controlled products is available in the Agricultural and Veterinary Chemicals Code Regulations 1995 (Agvet Code Regulations) and further information is available in the date-controlled agricultural chemical products guideline.

2. Design of stability testing trials

2.1. Size and number of batches

Stability testing should be conducted on laboratory-, pilot- or production-scale batches of a product. Batch sizes of less than 5 kilograms or 5 litres are normally not acceptable for use in stability testing, except when a normal production batch is this size. The formulation is to be the same as that proposed for registration in Australia.

Please include the following information in a stability study:

• Product name
• Batch identity
• Batch size
• Date of manufacture
• Containers used for storage of the samples during the study (size, construction material and type of container)

2.2. Storage conditions and duration

Storage stability trials may include accelerated or real-time tests, or both. Real-time testing is generally conducted for a product that may be unstable at high temperatures, and is generally a requirement for date-controlled products. Products containing microbial active constituents are usually date-controlled, not generally stable at the elevated temperatures typically used in accelerated testing, and therefore real-time testing is almost always necessary.

For some formulations, studies at lower temperatures may be necessary due to the instability of the formulation at higher temperatures (this should be reflected in the recommended storage conditions). Liquid formulations should be tested at low temperatures (0 ± 2˚C or lower). This is to demonstrate that the product does not change at low temperatures, for example, specific components may crystallise or separate at low temperatures.

For capsule suspension products, freeze-thaw cycling testing should be performed in order to confirm that the integrity of the capsules will not be adversely affected by freezing and re-thawing.

2.3. Accelerated testing

Stability tests at elevated temperatures are designed to increase the rate of chemical degradation or physical change in a product in order to obtain information on the shelf life of a product in a shorter time than a real-time study. Accelerated testing involves extrapolations from higher to lower temperatures, and from shorter to longer storage periods. For most agricultural chemical products, accelerated storage stability data is sufficient, without the provision of real-time storage stability data.

The FAO/WHO pesticide specifications recommend testing of relevant product parameters before and after storage for 14 days at 54˚C so any potential changes can be detected. In some situations, an alternative time-temperature regime, such as those listed in Table 2, may be used. For example, aerosol products are commonly tested at 40˚C for 8 weeks due to the safety issues associated with this type of formulation being exposure to temperatures above 50˚C.

Table 2

Accelerated storage temperatures and duration of stability trials
Temperature	Duration	Comments
54˚C	14 days	Generally preferred testing regime (CIPAC MT 46.3)
50˚C	4 weeks
45˚C	6 weeks
40˚C	8 weeks	Commonly used for aerosol products
35˚C ±2˚C	12 weeks
30˚C ±2˚C	18 weeks

Products that exhibit an adequate stability profile at 40˚C to 54˚C are likely to be stable under normal storage conditions (at or above 25˚C) for at least 2 years.

Appropriate justification should be provided for use of a temperature regime other than 2 weeks at 54˚C (or 8 weeks at 40˚C for aerosols). This is particularly important for the 2 lowest temperature regimes, where summer temperatures, particularly in northern areas, commonly reach 30 to 35˚C. Part of the justification may include lower recommended storage temperatures.

It is recommended that samples of the formulation be taken before and after the MT 46.3 test. The 2 samples (time zero and 14 days for 54˚C trials) may be analysed concurrently after the test. This will reduce the analytical error of 2 separate analyses on different days, and/or by different analysts.

2.4. Real-time testing

Data from accelerated stability studies can provide a useful indication of a product’s stability, but in some cases, products may pass this test and yet still be unstable in long-term storage.

In certain situations, stability data generated at ambient temperatures over a period of 2 years (real-time) may be more appropriate than accelerated testing. For example, where a proposed product has a tendency to cake over time, or is subject to contamination as a result of bacterial or fungal growth, accelerated testing would not be suitable to demonstrate the product’s stability.

Real-time testing is normally performed at, or above 25˚C, with storage for at least 2 years. Testing should at least be conducted at time zero, and at the end of the storage period. However, applicants may wish to consider further testing the product at intermediate time points (for example, after 6, 12 and 18 months storage for a 2-year study), particularly if the period of stability of the product is in doubt.

Real-time data are generally required for date-controlled agricultural chemical products.

Depending on the product’s formulation type and packaging material, standardised relative humidity and light exposure conditions may also be recommended during testing.

2.5. Low temperature stability testing

Liquid formulations (including capsule suspensions, emulsifiable concentrates, oil-in-water emulsions, micro-emulsions, soluble concentrates, and suspension concentrates) may be adversely affected by storage at low temperatures, resulting in crystallisation of active constituent(s), significant changes in viscosity, and/or phase separation of emulsions.

In some places in Australia, night temperatures regularly reach 0˚C, or lower. Therefore, liquid formulations should be tested at 0˚C ± 2˚C or lower, for 7 days. The effect of low temperatures on stability should be determined and reported according to the Collaborative International Pesticide Analytical Council (CIPAC) method MT 39.3 (liquid formulations).

For capsule suspension formulations, the capsule walls may break as a result of repeated freezing and thawing (thus releasing the active into the suspending liquid). Freeze-thaw cycling testing should be undertaken.

Note: Stability data generated at low temperatures are not required if the product label contains includes a warning against exposure to low temperatures. However, the APVMA needs to be satisfied that such a restriction is practical, and suitable argument should be provided. For example, non-provision of low temperature data is more likely to be acceptable for a household insecticide spray, which would generally be stored in a kitchen or laundry, and is unlikely to be exposed to freezing temperatures when compared to a herbicide for use in cereals, which is likely to be stored during winter in unheated and uninsulated sheds.

2.6. Test parameters

The stability profile of an agricultural chemical product is determined by monitoring a combination of chemical and physical properties on storage. Monitoring the content of the active constituent alone is insufficient to make any reliable prediction as to the stability of the product. Over prolonged storage, a product may not exhibit a decline in the concentration of the active constituent, yet the important physical properties (for example, wettability or suspensibility) may have changed as such to compromise the performance of the product.

This guideline includes test parameters for each formulation type. In order to adequately demonstrate product stability, all relevant parameters should be examined in a stability trial. If certain parameters are not addressed, scientific argument should be provided in lieu.

Note that these test parameters have been derived from the FAO/WHO pesticide specifications. For formulation types not listed in this guideline, it is recommended that you seek advice from the APVMA in the form of an enquiry, pre-application assistance application, or Item 25 technical assessment before commencing a stability trial.

2.7. Containers

The effects of a formulation on its primary packaging, and vice versa, is important. Products should be packaged in the same containers (materials and pack size) that are proposed for the marketing of the final product. If the product is to be marketed only in containers in which stability testing would be impractical (for example, because they are too large), then stability trials in smaller containers of the same materials and construction may be used, and data extrapolated to larger containers.

The packaging materials, size of the container, and the quantity of the product in the container used in stability trial should be provided as part of the stability trial information.

Containers should be examined after the trial storage period to ensure that no significant interaction with the formulation (affecting the stability or integrity of the packaging material) has taken place during storage.

2.8. Product in water-soluble bags

When a product is packaged in water-soluble bags or sachets, effects on the physical characteristics of a product often occur. When this type of packaging is proposed, relevant physical tests should be conducted in the presence of the soluble bag material, using the same ratio of formulation to bag material as will occur in a spray tank, or other application equipment. In addition, testing of the dissolution characteristics of water-soluble bags should be carried out using CIPAC method MT 176. The dissolution time should be reported.

Leakage and/or the effects of the formulation on the water-soluble bags should be examined. Where multiple bags are to be packaged in a single container, evidence should be provided that the integrity of the water-soluble packaging is not affected by the opening and resealing of the outer packaging, or by moisture entering the packaging through routine use. This may be achieved by storing a multi-bag pack at 25˚C over a 6-month period, and periodically removing a water-soluble bag until all the bags have been removed. The integrity of the water-soluble bags should be examined upon removal. In the resulting report, the time interval between openings, and the approximate duration the container was open should be specified.

The packaging material of products packaged in a water-soluble packs is treated as a component of the formulation. Therefore, if the product is currently registered in non-water soluble packaging, a change to water-soluble packaging would require additional stability trials examining the product packaged in water-soluble bags.

2.9. Analytical methods and validation data

2.9.1. Determination of active constituent content and relevant impurities

Full details of the analytical methods used to monitor a product during stability trials should be provided, except where you have used collaboratively tested standard methods for the analysis (CIPAC, Association of Official Analytical Chemists, etc.). Compendial methods such as CIPAC methods are regarded as validated, and do not require full revalidation.

The APVMA recommends that available analytical methods for a particular formulation, described in official and recognised publications such as CIPAC handbooks and AOAC, be used. These methods are legally recognised as regulatory methods.

For further details of the necessary degree of method validation, see the separate guideline on validation of analytical methods.

The following information should be included:

• Instrumentation
• Sample preparation
• Method of extraction of the active constituent from the product
• Reference standards and reagent preparation
• Validation data
• Copies of representative chromatograms (if applicable)
• Representative calculations

Alternative analytical methods may be used in place of regulatory methods. Appropriate validation data is required for such methods. The type of validation data required is dependent on the analytical techniques used, but will typically include demonstration of linearity over a suitable concentration range, specificity, precision and accuracy.

See the separate guideline on validation of analytical methods for further information.

2.9.2. Determination of physical properties

The results and interpretation of measurements of physicochemical properties are highly dependent on the analytical procedures used. The APVMA recommends that standard CIPAC, or equivalent accepted methods are used to measure the physicochemical properties of agricultural chemical products.

Validation data are not required for CIPAC, or other, appropriate compendial method’s physicochemical tests. If in-house company, or other methods are used for physicochemical property testing, a full description of the procedures should be provided, together with appropriate validation data. This may include a comparison between the officially recognised methods (CIPAC handbooks and the AOAC manual methods) and the in-house method, with comment on any differences, and the significance of any differences.

3. Test parameters for products

The data and/or testing parameters that the APVMA adopts are derived from the FAO/WHO pesticide specifications.

3.1. Active content

For stability testing of most products, testing of the active content before and after storage using a suitable specific chemical analytical method, is required.

In some specific cases, chemical analyses of the active content before and after storage may not be required. Examples include:

• highly acidic or caustic dairy sanitisers containing nitric acid and sulfamic acid, nitric acid and phosphoric acid, or alkaline salt blends. Here, the actives generally do not require chemical testing, as the activity of the product before and after storage can be demonstrated through measurement of pH, and/or total acidity/alkalinity
• acetic acid weedkillers – stability of these chemicals can generally be demonstrated by measurement of pH before and after storage
• spray adjuvants containing blends of non-ionic surfactants and paraffinic oils or canola fatty acid methyl/ethyl esters – stability of these can be sufficiently demonstrated by measurement of physicochemical properties alone (for example, appearance, emulsion stability, pH, persistent foam, and packaging stability).

Biological products such as those containing Bacillus thuringiensis as the active should be tested using suitable methods such as a colony-forming unit's assay, or an insect biopotency test.

For products demonstrating good stability, significant changes in active content should not be observed during real-time or accelerated stability studies.

However, simply remaining within the allowable variation for the active content (as defined in the Agvet Code Regulations) is not sufficient in itself, as these margins are intended to allow for variation in batch-to-batch manufacturing processes and in sampling; not to account for degradation during storage.

The active ingredient content should, in general, not decline by more than 5% from the level measured initially in accelerated or real-time testing. Further information and justification should be provided if the level of degradation exceeds 5%.

Measures taken to demonstrate and/or justify the quality, safety and efficacy of a formulation that exhibits high levels of degradation during storage could include the following:

• Identification and quantification of degradation products.
• Inclusion of a manufacturing overage not greater than 10% of the label claim to allow for degradation.
• Registration of the product subject to a condition of inclusion of an expiry date shorter than the standard 2 years from the date of manufacture.
• Conducting efficacy studies on aged batches of product to show that acceptable levels of efficacy are retained despite the decline in active content.

3.2. Content of relevant impurities

For some active constituents, testing of levels of toxicologically significant breakdown products, or impurities likely to accelerate the formation of toxicologically significant breakdown products (for example, water in diazinon) before and after storage may be required.

Some examples of toxicologically significant impurities that can form or increase in a formulated product during storage are tabulated below.

Table 3

Active constituent	Relevant impurities
Diazinon	Water O,O,O',O'-tetraethyl thiopyrophosphate (O,S-TEPP) O,O,O',O'-tetraethyl dithiopyrophosphate (S,S-TEPP)
Dimethoate	O,O,S-trimethyl phosphorodithioate Omethoate Isodimethoate Water
Mancozeb, metiram, propineb, zineb	Ethylene thiourea

Impurities must be measured using suitable methods supported by appropriate validation data. Where appropriate, compendial methods should be used (for example, CIPAC MT30.5 is a compendial method commonly used for determination of trace levels of water in formulations).

Levels of impurities must be within specified limits before, and after storage. Determination of suitable specified limits that can be justified from a human safety perspective can be sourced from the APVMA active constituent standards, or the FAO pesticide specifications. You should bear in mind that impurity limits in the APVMA active constituent standards are established for the technical active, not a formulated product, and appropriate conversion factors need to be applied if setting limits on the basis of g/kg or g/L in a formulation.

3.3. Appearance and physical state

These tests are performed visually, and are described in qualitative terms such as solid, liquid, suspension etc.

3.3.1. Colour

The following test methods are recommended:

• American Society for Testing and Materials (ASTM), Standard method for specifying colour by the Munsell system D-1535.
• ASTM Standard method for specifying colour of transparent liquids (Gardner Colour Scale, D-1544).

A visual description of colour is also acceptable.

3.3.2. Odour

This test is performed organoleptically and involves the use of descriptive terms (for example, thymol-like odour), characteristics of aromatic compounds (for example, garlic-like).

3.4. Acidity or alkalinity and pH

This test is recommended for any product where acidity or alkalinity and pH are relevant parameters for the quality of the product. Where relevant (that is, when the product is to be applied as an aqueous dilution), the pH of a 1% aqueous dilution, emulsion or dispersion of the product should be determined and reported according to CIPAC method MT 75.3. A change in pH during storage can give an indication of instability of the active substance or product.

The acidity or alkalinity is determined by titration with standard acid or alkali according to CIPAC method MT 31.

3.5. Wettability

Wettability of solid products that are diluted for use (for example, wettable powders, water-soluble powders, water-soluble granules and water-dispersible granules) is determined to ensure the product is adequately wetted prior to use.

The CIPAC method for determination of wettability is MT 53.3.

3.5.1. Acceptable limits for wettability

The wettability of a product is considered acceptable if there is complete wetting within one minute, without swirling.

If the product falls outside these limits, evidence should be provided to demonstrate the product has acceptable dispersion in the spray tank, or other, suitable application equipment.

3.6. Persistent foaming

Persistent foam is a measure of the amount of foam likely to be present in a spray tank, or other application equipment, following the dilution (with water) of the product in accordance with the label instructions.

The CIPAC method for persistent foaming is MT 47.1 or 47.2.

Although MT 47.2 was standardised for the determination of persistent foam in suspension concentrates, it is also applicable to other products that are dispersed in water.

3.6.1. Acceptable limits for persistent foaming

The following acceptable limits apply:

• MT 47.1 – maximum 25 mL foam after one minute.
• MT 47.2 – maximum 60 mL foam after one minute.

Where levels of persistent foam exceed the limits, further data or scientific argument will be required to demonstrate that the product can be mixed and applied without unacceptable risk to the environment or the operator, as a result of spillages or contact with excessive foam escaping the tank. This could take the form of a field-scale test, mixing the product in commercial spraying equipment to demonstrate that foam levels are acceptable in practice.

3.7. Suspensibility

Suspensibility of water-dispersible products (for example, wettable powders, water-dispersible granules and suspension concentrates) is determined to demonstrate that a sufficient amount of the active substance is suspended in spray liquid to produce a satisfactory, homogeneous mixture during spraying.

The following CIPAC methods apply:

• MT 15.1 – wettable powders.
• MT 161 – aqueous suspension concentrates.
• MT 168 – water-dispersible granules.
• MT 177 – water-dispersible powders.
• MT 184 – formulations forming suspensions on dilution with water.

For the determination of suspensibility, chemical assay (active suspensibility) is the only fully reliable method to measure the mass of the active substance remaining in suspension. However, gravimetric determination (total suspensibility), or solvent extraction determination may be used on a routine basis, provided that these methods have been shown to give equivalent results to those of the chemical assay.

When the solvent extraction method is used, the product should be assayed using the same technique to allow comparison of the results.

Where there is more than one insoluble active substance present in the product, chemical assay (active suspensibility) is the only method acceptable to demonstrate suspensibility.

The suspensibility test should be performed at both the highest and lowest dilutions recommended on the product label.

3.7.1. Acceptable limits for suspensibility

The mean measured active suspensibility should not be less than 60%, and not greater than 105%.

If a product falls outside these limits, evidence should be provided demonstrating that the product is homogeneous on application when applied with appropriate equipment (for example, determination of active content in spray at the beginning, middle and end of a spraying operation).

3.8. Spontaneity of dispersion (suspension stability)

The dispersion spontaneity of water-dispersible products (for example, water-dispersible granules or suspension concentrates) is determined in order to demonstrate a product is easily, and rapidly dispersed when diluted with water.

The following CIPAC methods apply:

• MT 160 – suspension concentrates.
• MT 174 – water-dispersible granules.

Chemical assay is the only reliable means to measure the mass of the active substance in suspension. However, gravimetric determination or solvent extraction determination may be used on a routine basis, provided it can be shown that these methods give equivalent results to those of a chemical assay.

When using the solvent extraction method, the product should be assayed using the same technique to allow for a comparison of the results.

Where there is more than one insoluble active substance present in the product, chemical assay is the only method acceptable to demonstrate spontaneity of dispersion.

3.8.1. Acceptable limits

The mean measured active suspensibility, or dispersibility should not be less than 60%, and not greater than 105%.

Where results fall outside these limits, evidence should be provided to demonstrate that a product is homogeneous on application using appropriate application equipment.

3.9. Dilution stability

Dilution stability is determined to ensure water-soluble products dissolve readily and, when diluted, produce stable solutions without precipitation, flocculation, etc.

The following CIPAC methods apply:

• MT 179 – degree of dissolution and solution stability.
• MT 41 – dilution stability of herbicide aqueous solutions.

3.9.1. Acceptable limits for dilution stability

• MT 41 – no more than a ‘trace’ of sediment after 30 minutes.
• MT 179 – max 2% retention on a 75 μm sieve.

Where results fall outside these limits, evidence should be provided demonstrating the material separated will not block the nozzles of application equipment.

3.10. Dry sieve test

The dry sieve test is designed to determine the particle size distribution of dustable powders and granules intended for direct application.

The following CIPAC methods apply:

• MT 59.1 dusts.
• MT 59.2 granular formulations.
• MT 170 water-dispersible granules.

3.10.1. Acceptable limits for the dry sieve test

Maximum 5% is retained on a 75 µm sieve (dustable powders).

For dustable powders, if 5% or more of the product is retained on a 75 micrometre (μm) sieve, the active content of material remaining on the sieve should be determined to demonstrate there was no separation of the active substance from the carrier.

3.11. Wet sieve test

For water-dispersible products, a 75 micrometre (μm) wet sieve test should be conducted. A wet sieve analysis determines the quantity of particles in a formulation diluted in water, collected on a screen.

The following CIPAC method applies:

• MT 185 – wet sieve test, a revision of methods MT 59.3 and MT 167.

The residue remaining on a sieve is determined following dispersion to ensure that no unacceptable residue remains that may cause the blockage of nozzles in application equipment.

This test is applicable to wettable powders, suspension concentrates, water-dispersible granules, aqueous capsule suspensions, dispersible concentrates, suspo-emulsions, water-soluble granules and water-soluble powders.

3.11.1. Acceptable limits for the wet sieve test

Maximum 2% retained on a 75 µm sieve.

Where a product falls outside these limits, evidence should be provided demonstrating the product may be satisfactorily applied using appropriate application equipment, with no blockage.

3.12. Particle size distribution

You should determine the nominal size range of solid materials for direct application (for example, dustable powders and granules) and solid materials for dispersion in water (for example, wettable powder and granules). These data are used to assess if an acceptable proportion of the product is within an appropriate size range.

The following methods apply:

• CIPAC MT 170 – water-dispersible granules.
• CIPAC MT 187 – particle size analysis by laser diffraction.
• OECD method 110 – powders or dusts.

3.13. Dust content

The dust content of solid preparations is determined to ensure the risk to operators is acceptable (for example, when transferring the product from the primary pack into a mixing tank), and to determine the potential for blockage of application equipment.

The following methods apply:

• CIPAC method MT 171 – granular products.
• OECD method 110 – powders or dusts.

MT 171 describes 2 methods for the determination of dustiness, but the gravimetric method is regarded as the reference method.

3.13.1. Acceptable limits for dust content

If 1% by weight of the preparation has a particle size of less than 50 µm, you should provide inhalation toxicity data.

3.14. Emulsifiability, re-emulsifiability and emulsion stability

For products that form emulsions, data on emulsifiability, emulsion stability and re-emulsifiability are used to determine whether a product forms, and maintains a stable emulsion.

The following CIPAC methods apply:

• MT 36.1 – 5% dilution.
• MT 36.2 – 1% dilution.
• MT 36.3 – emulsion characteristics and re-emulsification properties. 
• MT 173 – 0.1% to 2% dilution.

MT 36.1 is designed to be conducted over a 24-hour period. If no separation of cream or oil is observed after 2 hours, then no further testing is required. However, if separation is observed, you should perform the 24-hour test.

For a dilute emulsion, MT 173 is the preferred method. However, MT 36.1 may be used as a screening method. If no separation of a 5% dilution is seen after 2 hours, then no further testing is required. The test should be conducted in CIPAC waters A and D.

3.14.1. Acceptable limits for emulsifiability, re-emulsifiability and emulsion stability

• MT 36.1 – maximum 2 mL cream, trace of oil after 30 minutes; if any separation is observed, re-emulsification should be complete after 24 hours.
• MT 173 – minimum 98% after 4 hours; maximum 102% after 4 hours.

If a product falls outside of these limits, evidence should be provided to demonstrate that the product remains homogeneous when applied with the appropriate application equipment. If more than a trace of oil separates, re-formulation of the product should be considered.

3.15. Dispersion stability of suspo-emulsions

Data should be provided to demonstrate that a sufficient amount of active constituent is homogeneously dispersed in spray liquid to produce an effective, uniform mixture during spraying.

The following CIPAC method applies: MT 180.

3.15.1. Acceptable limits for stability of suspo-emulsions

Maximum 2 mL cream, no more than a trace of oil after 30 minutes. If any separation is observed, re-emulsification should be complete after 24 hours.

If a product falls outside these limits, evidence should be provided demonstrating that the product remains homogeneous when applied with the appropriate application equipment. If more than a trace of oil separates, re-formulation of the product should be considered.

3.16. Pourability (rinsability) of suspension concentrates

Data are required to demonstrate that a user can make use of the maximum amount of the product in the container, and that an excessive amount of the product does not remain in the container. This test should be conducted with suspension concentrates, capsule suspensions and suspo-emulsions.

The following CIPAC methods apply:

• MT 148.
• MT 148.1 (revised method).

3.16.1. Acceptable limits for pourability (rinsability) of suspension concentrates

Maximum 5% residue; maximum 0.25% rinsed residue.

If a product is outside these limits, evidence should be provided on the level of residue remaining in the commercial pack following recommended rinsing procedures.

3.17. Attrition and friability

Attrition is defined as the wearing away of the surface of a granule by friction or impact, particularly by granule-to-granule interaction.

Friability is defined as the tendency of a granule to crumble and break down into smaller particles.

Data are required to determine whether a granular material is sufficiently robust under normal conditions of use and transport.

The following CIPAC methods apply:

• MT 178 – measures attrition resistance of granules.
• MT 178.2 – measures attrition resistance of dispersible granules.

3.17.1. Acceptable limits for attrition and friability

If a material has an attrition resistance of less than 98%, evidence is required that the material may be satisfactorily applied with application equipment.

3.18. Viscosity

Viscosity is a property of fluids that describes the resistance offered to a shearing force under laminar flow conditions; for example, resistance to slow stirring, or to flow through a capillary, or narrow channel.

The kinematic viscosity of a liquid formulation for direct application (ultra-low-volume products) should be determined. For Newtonian fluid, the viscosity at any shear rate should be conducted. For non-Newtonian fluids (for example, a non-drip paint), viscosity values should be provided for at least 2 different shear rates.

The following CIPAC methods apply:

• MT 22.
• MT 114.

3.19. Flowability

The following methods apply:

• CIPAC method MT 44.
• OECD method MT 172.

3.19.1. Acceptable limits for flowability

The sample should flow through the sieve after a maximum of 5 liftings.

3.20. Dissolution rate of water-soluble bags

The dissolution rate of water-soluble bags should be carried out to demonstrate that particles of water-soluble material will not block the nozzles of the application equipment.

The following CIPAC method applies:

• MT 176.

3.20.1. Acceptable limits for the dissolution rate of water-soluble bags

The dissolution rate of water-soluble bags is 30 seconds.

3.21. Disintegration time and degree of dispersion or dissolution

Data are required to demonstrate that soluble or dispersible tablets disintegrate rapidly upon addition to water, and that the formulation is readily dispersed or dissolved.

4. Parameters to be tested in stability trials

In addition to the appearance and content of an active constituent, relevant physicochemical properties should be monitored before and after storage, according to the formulation type. The APVMA will update the relevant test parameters for additional formulation types listed in the Formulation Types guideline.

Shelf life specifications are drawn from the physical properties mentioned in the FAO/WHO pesticide specifications, and are applicable to any given formulation type.

The International codes used below are based on the Catalogue of pesticide formulation types and international coding system (CropLife International 2008). Individual CIPAC MT test parameters are listed with each individual formulation type.

Table 4

Dustable powders (DP)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Dry sieve test	MT 59.1
Packaging stability	Observation of packaging stability (Note: There should be no caking in the pack on storage)

Table 5

Powders for dry seed treatment (DS)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Dry sieve test	MT 59.1
Particle size distribution	OECD 110
Adhesion to seeds	Appropriate validated method
Packaging stability	Observation of packaging stability

Table 6

Granules (GR)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Pour and bulk density	MT 186
Particle size distribution	MT 58.3
Dust content	MT 171
Friability and attrition characteristics	MT 178
Release rate of active constituent	Suitable validated method
Packaging stability	Observation of packaging stability (Note: There should be no loss of granule integrity or caking on storage)

Table 7

Tablets for direct application (DT)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Tablet integrity	Visual observation (Note: No broken tablets.)
Tablet hardness	No CIPAC method
Degree of attrition	MT 193
Packaging stability	Observation of packaging stability

Table 8

Wettable powders (WP)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Wet sieve test*	MT 185
Suspensibility*	MT 184
Wettability*	MT 53.3
Persistent foam*	MT 47.2
Dissolution of water-soluble bags	MT 176 (Note: Only if the product is packaged in a sealed water-soluble bag)
Packaging stability	Observation of packaging stability (Note: There should be no caking in the pack on storage)

* If the product is packaged in a water-soluble bag, the wet sieve, suspensibility, wettability, and persistent foam tests should be performed using a solution consisting of the product and water-soluble bag in the same ratio as that found in the recommended application specification.

Table 9

Water-dispersible powders for slurry seed treatments (WS)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Wet sieve test	MT 185
Wettability	MT 53.3
Persistent foam	MT 47.2
Dissolution of water-soluble bags	MT 176 (Note: Only if the product is packaged in a sealed water-soluble bag)
Packaging stability	Observation of packaging stability

Table 10

Water-dispersible granules (WG)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Wet sieve test*	MT 185
Degree of dispersion	MT 174
Suspensibility*	MT 184
Wettability*	MT 53.3
Persistent foam*	MT 47.2
Dust content	MT 171
Flowability	MT 172
Attrition resistance	MT 178.2
Packaging stability	Observation of packaging stability (Note: There should be no caking in the pack on storage)

* If the product is packaged in a water-soluble bag, the wet sieve, suspensibility, wettability, and persistent foam tests should be performed using a solution consisting of the product and water-soluble bag in the same ratio as that found in the recommended application specification.

Table 11

Water-dispersible tablets (WT)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Tablet integrity	Visual observation (Note: No broken tablets.)
Suspensibility	MT 184
Disintegration time	Appropriate method
Wet sieve test	MT 185
Persistent foam	MT 47.2
Packaging stability	Observation of packaging stability

Table 12

Emulsifiable granules (EG)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Wettability	MT 53.3
Dispersion stability	MT 180
Wet sieve test	MT 185
Dustiness	MT 171
Persistent foam	MT 47.2
Packaging stability	Observation of packaging stability

* If the product is packaged in a water-soluble bag, the wettability, degree of dissolution, solution stability, and persistent foam tests should be performed using a solution consisting of the product and water-soluble bag in the same ratio as that found in the recommended application specification.

Table 13

Emulsifiable powders (EP)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Wettability	MT 53.3
Dispersion stability	MT 180
Wet sieve test	MT 185
Persistent foam	MT 47.2
Packaging stability	Observation of packaging stability

* If the product is packaged in a water-soluble bag, the wettability, degree of dissolution, solution stability, and persistent foam tests should be performed using a solution consisting of the product and water-soluble bag in the same ratio as that found in the recommended application specification.

Table 14

Water-soluble powders (SP)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Persistent foam*	MT 47.2
Wettability*	MT 53.3
Degree of dissolution and solution stability*	MT 179
Dissolution of water-soluble bags	MT 176 (Note: Only required if the product is packaged in a sealed water-soluble bag)
Packaging stability	Observation of packaging stability (Note: There should be no caking in the pack on storage)

* If the product is packaged in a water-soluble bag, the wettability, degree of dissolution, solution stability, and persistent foam tests should be performed using a solution consisting of the product and water-soluble bag in the same ratio as that found in the recommended application specification.

Table 15

Water-soluble powders for seed treatment (SS)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Degree of dissolution and solution stability	MT 179
Packaging stability	Observation of packaging stability (Note: There should be no caking in the pack on storage)

Table 16

Water Soluble Granules (SG)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Dust content	MT 171
Degree of dissolution and solution stability*	MT 179
Persistent foam*	MT 47.3
Attrition resistance	MT 178.2
Flowability	MT 172.1
Dissolution of water soluble bags	Comment: Only for the product packaged in a sealed water soluble bag
Packaging stability	Observation of packaging stability

* If the product is packaged in a water-soluble bag, the persistent foam, degree of dissolution, and solution stability tests should be performed using a solution consisting of the product and water-soluble bag in the same ratio as that found in the recommended application specification.

Table 17

Water-soluble tablets (ST)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Tablet integrity	Visual observation (Note: No broken tablets.)
Degree of dissolution and solution stability	MT 179
Wet sieve test	MT 185
Disintegration time	Appropriate method
Persistent foam	MT 47.2
Degree of attrition	MT 193
Packaging stability	Observation of packaging stability

Table 18

Soluble concentrates (SL)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Solution stability	MT 41
Persistent foam	MT 47.2
Low temperature stability	MT 39.3
Packaging stability	Observation of packaging stability

Table 19

Ready to use liquid formulations (AL)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Low temperature stability	MT 39.3
Packaging stability	Observation of packaging stability

Table 20

Solutions for seed treatment (LS)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Solution stability	MT 41
Low temperature stability	MT 39.3
Packaging stability	Observation of packaging stability

Table 21

Oil miscible liquids (OL)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity/alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Miscibility with hydrocarbon oil	MT 23
Low temperature stability	MT 39.3
Packaging stability	Observation of packaging stability

Table 22

Ultra low volume liquids (UL)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Low temperature stability	MT 39.3
Kinematic viscosity	MT 22, OECD 114
Packaging stability	Observation of packaging stability

Table 23

Emulsifiable concentrates (EC)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Emulsion characteristics	MT 36.1, MT 36.2, MT 36.3, MT 173 or MT 183
Persistent foam	MT 47.2
Low temperature stability	MT 39.3
Packaging stability	Observation of packaging stability

Table 24

Dispersible concentrates (DC)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Dispersion stability	MT 180
Wet sieve test	MT 185
Persistent foam	MT 47.2
Low temperature stability	MT 39.3
Packaging stability	Observation of packaging stability

Table 25

Emulsions, oil in water (EW)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Emulsion characteristics	MT 36.1, MT 36.2, MT 36.3, MT 173 or MT 183
Pourability	MT 148.1
Persistent foam	MT 47.2
Viscosity	MT 192
Low temperature stability	MT 39.3
Packaging stability	Observation of packaging stability

Table 26

Emulsions for seed treatment (ES)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Emulsion stability on dilution with water	Appropriate method
Persistent foam	MT 47.2
Low temperature stability	MT 39.3
Packaging stability	Observation of packaging stability

Table 27

Micro-emulsions (ME)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Emulsion characteristics	MT 36.1, MT 36.2, MT 36.3, MT 173
Persistent foam	MT 47.2
Low temperature stability	MT 39.3
Packaging stability	Observation of packaging stability

Table 28

Suspo-emulsions (SE)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Dispersion stability	MT 180
Pourability	MT 148.1
Wet sieve test	MT 185
Persistent foam	MT 47.2
Low temperature stability	MT 39.3
Packaging stability	Observation of packaging stability

Table 29

Suspension concentrates (SC)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Pourability	MT 148
Suspensibility	MT 184
Spontaneity of dispersion	MT 160
Wet sieve test	MT 185
Persistent foam	MT 47.2
Low temperature stability	MT 39.3
Packaging stability	Observation of packaging stability

Table 30

Suspension concentrates for seed treatment (FS)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Pourability	MT 148
Suspensibility	MT 184
Wet sieve test	MT 185
Persistent foam	MT 47.2
Low temperature stability	MT 39.3
Packaging stability	Observation of packaging stability

Table 31

Capsule suspensions (CS)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Pourability	MT 148
Suspensibility	MT 184
Spontaneity of dispersion	MT 160
Wet sieve test	MT 185
Persistent foam	MT 47.2
Low temperature stability	MT 39.3
Freeze - thaw stability	No CIPAC method (Note: Testing of stability parameters including acidity, alkalinity or pH range; pourability; suspensibility; spontaneity of dispersion; wet sieve test are required after a freeze-thaw cycle)
Packaging stability	Observation of packaging stability

Table 32

Oil-based suspension concentrates (OD)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Acidity or alkalinity or pH	MT 31 or MT 191 or pH range (MT 75.3)
Pourability	MT 148
Dispersion stability	MT 180
Wet sieve test	MT 185
Persistent foam	MT 47.2
Low temperature stability	MT 39.3
Packaging stability	Observation of packaging stability

Table 33

Water-soluble gels (GW)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Dilution stability*	MT 41
Packaging stability	Observation of packaging stability

* Only required if the preparation is to be dissolved in water.

Table 34

Mosquito coils (MC)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Average weight of coils	No CIPAC method
Burning time	No CIPAC method
Strength of coil	No CIPAC method
Packaging stability	Observation of packaging stability

Table 35

Vaporiser mats (MV)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Packaging stability	Observation of packaging stability

Table 36

Liquid vaporisers (LV)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Packaging stability	Observation of packaging stability (Note: No corrosion)

Table 37

Baits (including grain bait [AB], block bait [BB], granular bait [GB], ready-to-use bait [RB] and plate bait [PB])
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method Evidence of retention of biological efficacy may be acceptable
Packaging stability	Observation of packaging stability and integrity

Table 38

Products to be applied as smoke (including smoke tins [FD], smoke candles [FK], smoke cartridge [FP], smoke rodlet [FR], smoke tablet [FT], smoke generators [FU] and smoke pellets [FW])
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Burning time	No CIPAC method
Evidence of combustibility	No CIPAC method
Packaging stability	No CIPAC method

Table 39

Aerosol dispensers (AE)
Recommended test parameters	Relevant CIPAC method
Appearance (physical state, colour, odour)	No CIPAC method
Active constituent content	Appropriate validated method
Internal pressure	No CIPAC method
Discharge rate	No CIPAC method
pH	No CIPAC method
Clogging of aerosol dispenser valves	No CIPAC method
Spray pattern	No CIPAC method
Packaging stability	Observation of packaging stability (Note: No corrosion.)

5. References

Association of Official Analytical Chemists, Official methods of analysis of AOAC International, AOAC International, Arlington VA, United States.

ASTM International Annual book of ASTM standards; American Society for Testing and Materials, Philadelphia PA, United States.

CIPAC, CIPAC Handbooks, Black Bear Press, Cambridge, United Kingdom.

CropLife International 2008, Catalogue of pesticide formulation types and international coding system, Technical Monograph No. 2, 5th Edition, CropLife International, Brussels, Belgium.

JMPS 2010, Manual on the development and use of FAO and WHO specifications for pesticides, third revision of first edition, FAO/WHO Joint Meeting on Pesticide Specifications, the Food and Agriculture Organization and World Health Organization of the United Nations, Rome.

OECD, Guidance Document for Storage Stability Testing of Plant Protection and Biocidal Products, Series on Testing and Assessment No. 223, Series on Biocides No. 10, Organisation for Economic Cooperation and Development, Paris, France.